Introduction: Anal fissure is a common problem that causes significant morbidity in a young and otherwise healthy population. Surgical techniques (knife) like manual anal dilatation or lateral internal sphincterotomy, effectively heals most fissures within a few weeks, but may result in permanently impaired anal continence. This has led to the research for alternative non–surgical treatment, and thus ‘Chemical Sphincterotomy‘ (pill) is being investigated and used as the possible first line of treatment for anal fissures. The present study is thus designed to evaluate the role of topical Nitroglycerine ointment in cases of acute and chronic anal fissures. Materials & Methods: A prospective observational study was conducted at a tertiary healthcare centre. A total of 150 patients of acute/ chronic anal fissure were included in the study by consecutive type of non–probability sampling. Nitroglycerine ointment was administered to all patients. Patients in which medical management failed were posted for lateral internal sphincterotomy. The patients were followed up for a period of 6 weeks or until fissure is healed and were evaluated for relief of symptoms. Data was analyzed using SPSS software ver. 21. Results: Out of the total 150 patients, 75 were acute fissures and 75 were chronic fissures. Out of 75 cases of acute anal fissures, 73 (97.3%) responded to Nitroglycerine ointment and 2 (1.7%) required lateral internal sphincterotomy. Out of 75 cases of chronic anal fissures, 28 (37.3%) cases responded to Nitroglycerine ointment and 47 (62.7%) required lateral internal sphincterotomy. The relief of pain was faster with sphincterotomy than with NTG application as observed on comparison of mean pain score at the end of 6 weeks (0.51 vs 1.33; p<0.01). Conclusion: Nitroglycerine ointment is very effective in the treatment of acute anal fissures and also has a role in chronic fissures. Thus, Topical Nitroglycerine should be advocated as the first option of treatment for both, acute and chronic anal fissures. Internal sphincterotomy should be reserved for patients with therapeutic failure of pharmacological treatment and those with severe pain.